1. Field of the Invention
The present invention is directed to a harvester and in particular to a trunk shaker harvester having a shaker head with engagement members driven by synchronized motors.
2. Description of the Prior Art
Harvesters and fruit harvesters in particular use a wide variety of configurations for dislodging fruit, nuts and other crops from the plants. A well known configuration and method utilizes trunk shakers that engage the trunk of a plant or vine to shake loose the crops to be harvested. The shaker mechanisms take on several configurations such as force balanced shakers. Although know systems such force balanced shakers are effective in removing produce, there are several drawbacks. The required mass of the weights imparts unwanted vibration and forces to the chassis. Moreover, the mounting of the weights in an overhead position moves the drive and oscillations closer to the harvester chassis and further from the trunk or vine that is actually being shaken so that more of energy from the shaking mechanisms is conveyed to harvester and less to the plants.
In addition to positioning, the use of force balanced shakers requires greater weight. The greater weight of the drive mechanism compounds design capabilities as the increased weight requires a stronger shaker frame and assembly to dampen the desired movement of the shaker. The heavier frame and assembly also requires a stronger and heavier chassis to support the larger shaker. Therefore, the entire harvester weighs more and is less efficient, may cause additional damage and may require additional considerations for layout of over the row harvesters.
It can be seen then that a new and improved shaker mechanism for an over the row harvester is needed. Such a shaker should provide for imparting an oscillation with reduced weights and with less mass. Moreover, the drive assembly should use lighter weights, requiring a lighter frame for the shaker head and a lighter frame for the harvester. The oscillation should also be electronically synchronized between the various drive assemblies to maintain synchronization. This eliminates the need for mechanical synchronization, therefore reducing the weight of the synchronization system so that less reactive force is passed from the shaker head that must be absorbed by the harvester. The shaker drives should also be mounted on or the close to the plant engagement members to convey more of the energy and forces from the shaking mechanisms to the trunks or vines being shaken. The present invention addresses these problems, as well as others associated with shaker mechanisms for over the row harvesters.